REPTILIA. 
17 
features of the Sauropoda (Plate II). In end view the Wall-ease 
laterally compressed shape of the body is noteworthy, a 4. 
strange contrast to the relative bulkiness of the largest warm- Tabl ] e g ease 
blooded quadrupeds or mammals. The nostrils open on the Cases 
top of the head (Fig. 11), exactly as should be the case in an IL - 
air-breather spending most of its time under water. The 
three inner toes bear large claws, and the two outer toes are 
diminutive. Di'plodocus (“double beam”) is so named because 
each posterior chevron bone (i.e. bone to cover and protect the 
blood-vessels on the lower face of the tail) consists of two 
separate bars slung in the middle—an arrangement unknown 
Fig. 11. —Skull and mandible of a Sauropodous Dinosaur (Dijolodocus ),.left 
side-view, from the Upper Jurassic of Colorado, U.S.A.; one-sixth nat. 
size. The cleft at the summit of the head is the nostril, and the large 
round vacuity is the orbit. The diminutive brain-case is behind and 
partly between the orbits. (After 0. C. Marsh.) 
in any other animal when this Dinosaur was first discovered. 
In the Gallery of Fossil Reptiles many portions of closely 
similar Sauropoda are exhibited from English Jurassic and 
Wealden rocks. The finest specimen is the greater part of a Case L. 
tail, with the left hind limb and associated right fore limb of 
Cetiosaurus leedsi, discovered by Mr. Alfred N. Leeds in the 
Oxford Clay near Peterborough (Plate III.; Case L). The 
skeleton measures 10 feet 6 inches in height at the hip-region, 
and its total length when complete must have been nearly 
60 feet. Detached bones of the same species from Peter¬ 
borough, including a piece of the whip-like end of the tail, 
c 
